Food and Bioprocess Technology | 2019
Characterization of Water Binding Properties of Apple Pectin Modified by Instant Controlled Pressure Drop Drying (DIC) by LF-NMR and DSC Methods
Abstract
Effects of instant controlled pressure drop drying (DIC) on the hygroscopic behavior of water-soluble pectin (WSP), chelator-soluble pectin (CSP), and sodium-carbonate-soluble pectin (NSP) were explored to reveal the modification effect of DIC treatment on apple pectin and the correlations between water binding capacity and the inherent characteristic of pectin. The results showed that DIC treatment significantly increased the water binding properties of CSP even though it was decreased slightly in WSP and NSP. Meanwhile, the methylesterification degree (DE) of CSP decreased significantly by 43.04% whereas it was increased slightly in WSP and NSP. Although the effect of DIC on GalA contents and the changes in the functional group structures were negligible, the changes in the crystalline state of three pectin fractions were significant. The results suggest that there are strong correlations between the water binding properties and the DE and the crystalline state of the three pectin fractions after DIC drying.